Monazo compounds containing a 1-phenyl-2-pyrazoline coupling component

ABSTRACT

Disperse dyestuffs of the formula ##STR1## in which A/B denotes H, alkyl, C1 or O-alkyl, 
     R 1 , R 2 , R 3  denote H or alkyl, 
     R 4  denotes alkyl, aryl or COO-alkyl, 
     R 5  denotes alkyl or aryl, 
     Y denotes H or CN, 
     X denotes NO 2 , Cl, Br, CN or SO 2  -alkyl, 
     V denotes NO 2 , Cl, Br, COOR 5 , COR 5  CF 3  or alkyl and 
     Z denotes H, Cl, Br, SCN or CN, 
     are very color-strong and are suitable in particular for the dyeing of polyester by a wide range of methods.

The invention relates to virtually water insoluble nonionic azo dyestuffs of the formula ##STR2## in which, independently of one another, A/B denotes H, alkyl, Cl or O-alkyl,

R₁, R₂, R₃ denote H or alkyl,

R₄ denotes alkyl, aryl or COO-alkyl,

R₅ denotes alkyl or aryl,

Y denotes H or CN,

X denotes NO₂, Cl, Br, CN or SO₂ -alkyl,

V denotes NO₂, Cl, Br, COOR₅, COR₅, CF₃ or alkyl and

Z denotes H, Cl, Br, SCN or CN,

with the proviso that Z is Cl, Br, SCN or CN, if Y is H, and where the alkyl radicals, in whatever context they are mentioned, have 1 to 4 C atoms and the aryl radicals are preferably phenyl radicals which can be substituted by Cl or C₁ -C₄ -alkyl.

Those dyestuffs of the formula I are preferred in which

A denotes H, CH₃ or Cl,

B denotes H, CH₃, Cl or O-alkyl,

R₁ -R₃ denote H or alkyl,

R₄, R₅ denote alkyl or aryl,

Y denotes CN or H,

X denotes NO₂, Cl, Br, CN or SO₂ -alkyl,

V denotes NO₂, Cl, Br, COOR₅ or alkyl and

Z denotes H, Cl, SCN or CN and

in which the abovementioned provisos apply to Z and the alkyl or aryl radicals.

Those dyestuffs of the formula I are particularly preferred in which

A denotes H or CH₃,

B denotes H, CH₃ or Cl,

R₁ -R₃ denote H or C₁ -C₄ -alkyl,

R₄ denotes C₁ -C₄ -alkyl,

Y denotes CN or H,

X denotes NO₂, Cl, Br or CN,

V denotes NO₂, Cl, Br or C₁ -C₄ -alkyl (preferably CH₃) and

Z denotes H, SCN or CN,

with the proviso that Z is SCN or CN, if Y is H.

Very particular preference is given, on the one hand, to dyestuffs of the formula I in which

A denotes CH₃ or preferably H,

B denotes H, Cl or preferably CH₃,

R₁ -R₃ denote H or C₁ -C₂ -alkyl,

R₄ denotes C₁ -C₂ -alkyl,

Y denotes CN,

X denotes CN or NO₂,

V denotes Cl, Br or preferably NO₂, and

Z denotes H,

and, on the other hand, to those of the formula I in which

A denotes CH₃ or preferably H,

B denotes H, Cl or preferably CH₃,

R₁ -R₃ denote H or C₁ -C₂ -alkyl,

R₄ denotes C₁ -C₂ -alkyl,

Y denotes H,

X denotes CN or preferably NO₂,

V denotes NO₂ and

Z denotes CN or preferably SCN.

The novel azo dyestuffs of the formula (I) are prepared in a manner known per se, for example by coupling of diazotized anilines of the formula (II) ##STR3## onto coupling components of the formula (III) ##STR4## in which A, B, R₁ -R₅, Y, X, V, Z have the abovementioned meanings.

The diazotization is preferably carried out in concentrated sulphuric or phosphoric acid, or in glacial acetic acid and/or propionic acid.

The coupling components are known or can be prepared by methods known per se (cf., for example, GB-A 972,956, page 3, lines 28-30).

The CN- and SCN-containing dyestuffs are, however, preferably prepared by exchanging the halogen substituent in dyestuffs of the formula I in which at least one of the radicals X, Y, Z represents Cl, Br or I for a CN or SCN radical.

These nucleophilic exchange reactions are also known and described, for example, in the following patent literature:

DE-A 1,544,563=GB-A 1,125,683; DE-A 2,341,109 and 2,456,495, DE-A 1,809,921 and GB-A 1,255,367, GB Patent Specification 1,226,950 and DE-A 3,300,914.

The halogen/cyano exchange by means of copper(I) cyanide, zinc cyanide or mixtures of these cyanides in preferably polar aprotic solvents is preferred.

The azo dyestuffs according to the invention can be used for the dyeing of synthetic textile materials, in particular textile materials from secondary cellulose acetate and cellulose triacetate, and very particularly aromatic polyesters, such as, for example, polyethylene terephthalate, by the dyeing procedures customary for these types of fibre, using aqueous or non-aqueous liquors.

Moreover, the novel dyestuffs can also be used for the spin-dyeing and the dyeing in the mass of thermoplastics, for example polyesters, polystyrenes, polycarbonates and polyolefins.

The novel dyestuffs are also suitable for the use in textile and non-textile transfer printing.

The red to blue dyeings obtained are distinguished by a particularly clear shade in combination with good general fastness properties and high tinctorial strength.

EXAMPLE 1

Preparation of the dyestuff of the formula ##STR5##

50 g of 2,6-dibromo-4-nitroaniline are stirred into 73 ml of 93% strength sulphuric acid and diazotized at 30° C. with 31 ml of 40% strength nitrosylsulphuric acid. Stirring is continued for 3 hours. The diazonium salt solution obtained is poured onto 630 g of ice, and the nitrite excess is destroyed. 35.5 g of 1-(m-tolyl)-3,5,5-trimethylpyrazoline are added to this solution. Stirring is continued for 5 hours, the product is filtered off with suction and washed with water. Yield of the dibromo dyestuff: 82 g.

50 g of the dibromo dyestuff thus obtained are suspended in 120 ml of dimethylformamide. After the addition of 5.4 g of copper cyanide and 8.2 g of zinc cyanide, the mixture is heated at 105° C. for 5 hours. The product is precipitated with 180 ml of methanol, filtered off with suction, washed with methanol and water, and dried. This gives 27.2 g of the dyestuff of the formula 1; it dyes polyester fibers in a brilliant blue shade having good fastness properties.

Using an analogous or similar procedure, the dyestuffs listed in the following table are obtained; they dye polyester in the shades mentioned and the dyeings obtained have good fastness properties.

    __________________________________________________________________________          ##STR6##                         blue                                          ##STR7##                         blue                                          ##STR8##                         blue                                          ##STR9##                         blue                                          ##STR10##                        greenish blue                                 ##STR11##                        reddish blue                                  ##STR12##                        reddish blue                                  ##STR13##                        blue                                     10.                                                                                 ##STR14##                        blue                                          ##STR15##                        blue                                          ##STR16##                        blue                                          ##STR17##                        blue                                          ##STR18##                        blue                                          ##STR19##                        blue                                          ##STR20##                        greenish blue                                 ##STR21##                        reddish blue                                  ##STR22##                        reddish blue                                  ##STR23##                        blue                                     20.                                                                                 ##STR24##                        blue                                          ##STR25##                        reddish blue                                  ##STR26##                        reddish blue                                  ##STR27##                        reddish blue                                  ##STR28##                        reddish blue                                  ##STR29##                        reddish blue                                  ##STR30##                        reddish blue                                  ##STR31##                        bluish violet                                 ##STR32##                        bluish violet                                 ##STR33##                        reddish blue                             30.                                                                                 ##STR34##                        reddish blue                                  ##STR35##                        bluish red                                    ##STR36##                        bluish red                                    ##STR37##                        bluish red                                    ##STR38##                        bluish red                                    ##STR39##                        bluish red                                    ##STR40##                        bluish red                                    ##STR41##                        bluish red                                    ##STR42##                        bluish red                                    ##STR43##                        bluish red                               40.                                                                                 ##STR44##                        bluish red                                    ##STR45##                        reddish violet                                ##STR46##                        reddish violet                                ##STR47##                        reddish violet                                ##STR48##                        reddish violet                                ##STR49##                        reddish violet                                ##STR50##                        violet                                        ##STR51##                        reddish violet                                ##STR52##                        reddish violet                                ##STR53##                        reddish violet                           50.                                                                                 ##STR54##                        reddish violet                                ##STR55##                        blue                                          ##STR56##                        blue                                          ##STR57##                        blue                                          ##STR58##                        blue                                          ##STR59##                        blue                                          ##STR60##                        blue                                          ##STR61##                        reddish blue                                  ##STR62##                        reddish blue                                  ##STR63##                        blue                                     60.                                                                                 ##STR64##                        blue                                     __________________________________________________________________________ 

We claim:
 1. An azo dyestuff of the formula ##STR65## in which, independently of one another, A denotes H,B denotes H, or CH₃, R₁, R₂, denote C₁ -C₂ -alkyl, R₃ denotes H or C₁ -C₂ -alkyl, R₄ denotes C₁ -C₂ -alkyl, Y denotes CN, X denotes NO₂ or CN, V denotes NO₂, and Z denotes H.
 2. An azo dyestuff according to claim 1, whereinA denotes H, B denotes CH₃, R₁ and R₂ denote C₁ -C₂ -alkyl, R₃ denote H or C₁ -C₂ -alkyl, R₄ denotes C₁ -C₂ -alkyl, Y denotes CN, X denotes CN or NO₂, V denotes NO₂ and Z denotes H.
 3. An azo dyestuff according to claim 1, whereinA denotes H, B denotes CH₃, R₁ and R₂ denote C₁ -C₂ -alkyl, R₃ denotes H or C₁ -C₂ -alkyl, R₄ denotes C₁ -C₂ -alkyl, Y denotes CN, X denotes NO₂, V denotes NO₂ and Z denotes H.
 4. An azo dyestuff according to claim 1 of the formula ##STR66##
 5. An azo dyestuff according to claim 1 of the formula ##STR67##
 6. An azo dyestuff according to claim 1 of the formula ##STR68## 